Poor self-regulation (i.e., inability to harness cognitive, emotional or motivational resources to achieve goals) contributes to a number of unhealthy behaviors across the life course, including overeating, a lack of physical activity, smoking, alcoholism and substance abuse1-12 that are linked to poor long-term health. The self- regulation processes that generate the desire for such substances or that make it difficult t engage in healthy habits are theorized to begin very early in the lifespan. Targeting early self-regulation profiles that signal risk for engaging in unhealthy behaviors would allow more effective intervention. It is thus vital to identify bio- behavioral self-regulation processes thatare 1) evident early in life; 2) associated with behaviors that lead to poor health outcomes; and 3) modifiable. In response to RFA-RM-14-020, Science of Behavior Change: Assay Development and Validation for Self-Regulation Targets, we propose to assess self-regulation during pre-adolescence, a critical transition when children gain responsibility for managing their health choices and self-regulation becomes increasingly associated with health outcomes. Obesity is a complex health issue with early-emerging biological and behavioral precursors that are related to self-regulation; it is a good model for understanding a broad range of health conditions that require active self-management. Childhood obesity is also an ongoing public health crisis, with almost 25% of children overweight by age 4 years (35% by school- age).13 The goal of this proposal is to measure childhood self-regulation targets known to be associated with obesity risk and poor adherence to medical regimens and to assess whether intervening on these mechanisms can improve self-regulation. We propose to do so in a cohort of children with a high rate of obesity who have been extensively phenotyped for bio-behavioral self-regulation and obesity risk factors from early childhood. For the UH2 phase, the Aims are to, in over 250 low-income school-age children from extant ABC cohorts: Aim 1. Field-test measures to assess executive function (cool EF, hot EF, and food-specific hot EF), emotion regulation, and motivation as self-regulation targets relevant for health behavior. Aim 2. Validate measures of the above self-regulation targets against proximal constructs known to be associated with obesity and poor health outcomes (e.g., obesogenic eating behavior, blunted cortisol pattern). Aim 3. Develop and field-test interventions designed to address self-regulation targets using a Multiphase Optimization Strategy (MOST) design to detect intervention effectiveness and child or family factors (e.g., maternal education, family stress) that may moderate intervention effects. For the UH3 phase, the Aims are to, in 94 children drawn from pediatric subspecialty clinics: Aim 4. Test the hypothesis that the interventions developed in Aim 3 enhance self-regulation targets. Aim 5. Explore whether enhancing self-regulation targets predicts general and disease-specific medical regimen adherence (i.e., following weight management recommendations; taking medications).